I was afraid that if I post this on the Sikorsky X2 thread, people will crucify me for being off-topic (promoting other techs rather than the x2) about an already somewhat off-topic discussion, but if the mod think that it would fit in there, then please merge them together or something. Thanks!

EDit: Do I have to save the images down in order to attach them here? 'Cause now I can only link to the pages but i can't get the pix to show up on my post.

Rotor downwash is proportional to disc loading. The higher discloading will generate higher downwash velocities. Just take takeoff gross weight and divide by disc area and you get an idea of which one is worse.

Logged

All modern aircraft have four dimensions: span, length, height and politics. TSR.2 got the first three right - Sir Sydney Camm

The CGT-150, Carter's Gyroplane Transport with a 150' diameter rotor and wingspan, will be able to perform jump take offs and zero roll landings without a runway. It will not be able to hover like a helicopter, but the associated weight savings will give it an increased payload. At high speeds, it will unload its rotor onto very efficient high-aspect ratio wings and (in the process) slow the rotor to minimize profile drag and maximize flight efficiency. A hovering variant, the CHT-150, or Carter Heliplane Transport, would be able to operate like a helicopter. At high speeds, it will transfer to a gyroplane mode and operate just like the CGT-150. However, the gearbox required to power the rotor will increase the empty weight, and reduce the payload by about 20,000 lbs.

Both aircraft will be powered by two Pratt & Whitney F135 engines, the same as used in the Joint Strike Fighter. The gyroplane version will have an empty weight of around 140,000 lbs, while the heliplane version will have an empty weight of around 160,000 lbs, and both will have a max gross weight of 330,000 lbs. A fully loaded 18-wheeler could be driven up its ramp and parked inside (with room to spare), and then flown away - straight up. A military version could carry two fully loaded Stryker Vehicles, 1 Abrams tank, or 200 combat troops. Once airborne, with the rotor slowed and the lift transferred to the wings, flight efficiencies will approach those of fixed-wing aircraft. The CGT-150 is designed to cruise at 500 MPH at 30,000 ft altitude and carry a 140,000 lb payload for over 1000 miles.

The only new technologies needed to design the CHT-150 were proven in flight tests on the CarterCopter Technology Demonstrator (CCTD). The CCTD was built as a proof-of-concept demonstrator for both the Carter ultra-high-inertia rotor and the control system interface between the rotor and wings. Other innovations on the prototype include the Carter high efficiency prop with a computerized prop controller, and the extreme-energy absorbing landing gear. On the CHT-150, the 24-ft diameter 4-bladed version of the same prop will produce over 70,000 lbs of static thrust per prop (x 2 props). The CHT-150 version of the same landing gear with a 7 ft stroke will be able to absorb landing impacts up to 50 feet per second without damage to the aircraft or occupants.